Exogenous Spermidine Optimizes Nitrogen Metabolism and Improves Maize Yield under Drought Stress Conditions

This study was to explore the nitrogen metabolism and transcriptome mechanism of spermidine (Spd) under drought stress conditions. Firstly, maize variety Xianyu 335 (drought insensitive type) Fenghe 1 sensitive were chosen as experimental materials hydroponic The effects PEG-6000 combined with Spd application on studied. Secondly, we chose for field experiment. At flowering stage, normal water treatment moderate carried out, respectively. results showed that: (1) Hydroponics experiment that content NH4+ in leaves seedlings increased significantly, while NO3? nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT), dehydrogenase (GDH), glutamic oxaloacetic transaminase (GOT) pyruvic (GPT) significantly. can promote assimilation excess ammonia by enhancing activities assimilating enzymes GS/GOGAT GDH, (GOT GPT), effectively alleviate toxicity disorder induced stress. (2) Pot significantly promoted root growth stress, so improve absorption utilization nutrients. In addition, chlorophyll photosynthetic rate After exogenous Spd, green leaf area increased, senescence slowed down, dry matter accumulation after anthesis, resulting increase grain weight number per ear, finally yield.